Browsing by Author "Özdemir M."
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Item Heavy metal bioaccumulation by cultivated Agaricus bisporus from artificially enriched substrates(Springer Verlag, 1998) Tüzen M.; Özdemir M.; Demirbaş A.Cultivated Agaricus bisporus possess the ability to bioaccumulate seven heavy metals (Pb, Cd, Hg, Fe, Cu, Mn, and Zn). The cultivated champignon mushroom A. bisporus was grown in soil composts of 16 different compositions. An edible mushroom, A. bisporus was also cultivated on humic compost artificially fortified with the seven heavy metals at five different concentrations (0.1 mg/ kg, 0.5 mg/kg, 1.0 mg/kg, 3.0 mg/kg, and 10.0 mg/kg) and on control substrate (0 mg/kg) on a dry weight basis. The method of measuring bioaccumulation was flame atomic absorption spectrophotometry. © Springer-Verlag 1998.Item Heavy metal bioaccumulation by cultivated Agaricus bisporus from artificially enriched substrates(1998) Tüzen M.; Özdemir M.; Demirbaş A.Cultivated Agaricus bisporus possess the ability to bioaccumulate seven heavy metals (Pb, Cd, Hg, Fe, Cu, Mn, and Zn). The cultivated champignon mushroom A. bisporus was grown in soil composts of 16 different compositions. An edible mushroom, A. bisporus was also cultivated on humic compost artificially fortified with the seven heavy metals at five different concentrations (0.1 mg/ kg, 0.5 mg/kg, 1.0 mg/kg, 3.0 mg/kg, and 10.0 mg/kg) and on control substrate (0 mg/kg) on a dry weight basis. The method of measuring bioaccumulation was flame atomic absorption spectrophotometry. © Springer-Verlag 1998.Item Women's attitudes and expectations regarding gynaecological examination(2009) Yanikkerem E.; Özdemir M.; Bingol H.; Tatar A.; Karadeniz G.Objective: to describe women's expectations of doctors and nurses during gynaecological examination, to identify if women have a preference for the doctor's gender, to investigate women's feelings during examination, and to determine why women consult the gynaecological outpatient clinic. Design: a descriptive and cross-sectional study using a questionnaire administered face to face. Setting: this study was performed with women recruited from those making an appointment for gynaecological examination at the gynaecological outpatient clinic at Manisa Maternity and Child Hospital between September 2004 and February 2005. Participants: four hundred and thirty-three women who applied to the gynaecological outpatient clinic at Manisa Maternity and Child Hospital. Measurements: the questionnaire included questions about the women's socio-demographic and reproductive characteristics, feelings with regard to pelvic examination, expectations of doctors and nurses during gynaecological examination, preferences regarding the gender of the physician, and the reason for the gynaecological examination. Findings: more than one-half of women felt anxious or worried about their health situation during the pelvic examination (54.8%), and 41.8% of women said that they were embarrassed about having to undress. 45.5% of women reported that they would prefer a female doctor, only 4.2% of women would prefer a male doctor in their obstetric and gynaecological care, and the remaining women (49.9%) expressed no preference. Most women (62.1%) expected the doctor to explain their health situation after examination. 71.8% of women said that the nurse should have an understanding and gentle manner, and 28.2% of women stated that the nurse should offer information to the patient about the pelvic examination. Key conclusions: it was very important for the women to participate through receiving information during the gynaecological examination. When treated with respect, the women were able to have a positive relationship with the staff. This encourages the women to attend clinics for their own health needs. Gynaecological examination is an essential part of gynaecological care and the most common procedure in gynaecological practice. Many women in the world will have a gynaecological examination several times during their lives, from youth to old age. This study could contribute to improve health programmes to make the gynaecological examination situation more positive for women. © 2007 Elsevier Ltd. All rights reserved.Item Clinical and demographic features of hidradenitis suppurativa: a multicentre study of 1221 patients with an analysis of risk factors associated with disease severity(Blackwell Publishing Ltd, 2021) Özkur E.; Karadağ A.S.; Üstüner P.; Aksoy B.; Eşme P.; Çalışkan E.; Akoğlu G.; Kalkan G.; Demirseren D.D.; Polat M.; Ozden M.G.; Kılınç F.; Yalçınkaya İyidal A.; Kıvanç Altunay İ.; Türkmen M.; Uğurer E.; Baysak S.; Fettahlıoğlu Karaman B.; Mammadlı K.; Baykal Selçuk L.; Türkoğlu Z.; Atcı T.; Didar Balcı D.; Adışen E.; Temel B.; Aktan Ş.; Kaçar N.; Gündüz K.; Türel Ermertcan A.; Özdemir M.; Ünal Çakıter A.; Çölgeçen E.; Uçmak D.; Kelekçi H.; Ataseven A.; Durmaz K.; Kaya Özden H.; Engin B.; Yazıcı S.; Alpsoy E.Background: Hidradenitis suppurativa (HS) is a chronic, relapsing and debilitating inflammatory disease associated with profound morbidity. Aim: In this multicentre study, we investigated the demographic and clinical features of HS, and determined risk factors of disease severity. Methods: In total, 1221 patients diagnosed with HS from 29 centres were enrolled, and the medical records of each patient were reviewed. Results: The mean age of disease onset was 26.2 ± 10.4 years, and almost 70% (n = 849) of patients were current or former smokers. Mean disease duration was 8.9 ± 8.4 years with a delay in diagnosis of 5.8 ± 3.91 years. Just over a fifth (21%; n = 256) of patients had a family history of HS. The axillary, genital and neck regions were more frequently affected in men than in women, and the inframammary region was more frequently affected in women than in men (P < 0.05 for all). Acne (40.8%), pilonidal sinus (23.6%) and diabetes mellitus (12.6%) were the most prevalent associated diseases. Of the various therapies used, antibiotics (76.4%) were most common followed by retinoids (41.7%), surgical interventions (32.0%) and biologic agents (15.4%). Logistic regression analysis revealed that the most important determinants of disease severity were male sex (OR = 2.21) and involvement of the genitals (OR = 3.39) and inguinal region (OR = 2.25). More severe disease was associated with comorbidity, longer disease duration, longer diagnosis delay and a higher number of smoking pack-years. Conclusions: Our nationwide cohort study found demographic and clinical variation in HS, which may help broaden the understanding of HS and factors associated with disease severity. © 2020 British Association of DermatologistsItem EXPERIMENTAL ASSESSMENT and TOPSIS OPTIMIZATION of CUTTING FORCE, SURFACE ROUGHNESS, and SOUND INTENSITY in HARD TURNING of AISI 52100 STEEL(World Scientific, 2022) Rafighi M.; Özdemir M.; Şahinoǧlu A.; Kumar R.; Das S.R.In this work, initially, the raw AISI 52100 bearing steel was heat-treated to obtain 40 HRC and 45 HRC workpiece hardness. Further, dry hard turning tests were carried out to study the impact of workpiece hardness (H), cutting speed (v), feed (f), and depth of cut (a) on cutting force (Fy), surface roughness (Ra), and sound intensity (SI). An economically viable PVD-coated carbide turning tool was implemented for the experiments. The Taguchi L18 (2-3 mixed level) design of experiments was employed to establish the experimental plan in order to save the experimental time, energy, and cost of manufacturing. The results disclosed that the feed has the prevailing consequence on surface roughness with a 96.3% contribution, while it also significantly affects the cutting force with a contribution of 13.8%. The contribution of cutting speed and workpiece hardness on the cutting force was reported as 48.3% and 35.1%, respectively. Higher workpiece hardness required more energy for plastic deformation as a result the cutting force increases with leading hardness. The sound intensity was dominantly influenced by depth of cut (53.3%) and cutting speed (40%). Finally, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was performed to determine the optimum machining parameters. According to the TOPSIS, the optimum level of cutting parameters was predicted as 40 HRC hardness (H), 150m/min cutting speed (V), 0.15mm/rev feed (f), and 0.1mm depth of cut (a) while the optimal result of Fy, SI, and Ra were noted as 27.66N, 70.7dB, and 0.86μm individually. © 2022 World Scientific Publishing Company.Item Analysis and optimisation of the cutting parameters based on machinability factors in turning AISI 4140 steel(Taylor and Francis Ltd., 2022) Özdemir M.; Şahinoğlu A.; Rafighi M.; Yilmaz V.AISI 4140 alloy steel has high abrasion resistance, toughness, torsional, and fatigue strength. Different types of this alloy with different hardness are used to manufacture gears, crankshafts, collars, jigs, and milling spindles. In this study, turning tests were carried out on AISI 4140 steel using coated carbide inserts considering Taguchi L9 orthogonal array at three different cutting speeds, feed rates, and cutting depths. The output parameters were selected as cutting forces, surface roughness, current and sound intensity. According to the ANOVA results, feed rate was the most effective parameter on the cutting force and surface roughness. As the feed rate increases, the cutting force and surface roughness value enhance. The feed rate was also the most important factor affecting the current with 81.61% contribution, followed by cutting depth with 12.67% contribution. The cutting depth with 66.95% contribution has the highest impact on the sound intensity. It was followed by a feed rate with 26.07% contribution. According to the optimisation results, the experimental and the estimated values were significantly close to each other. © 2022 Canadian Institute of Mining, Metallurgy and Petroleum.Item Modeling and optimization of hard turning: predictive analysis of surface roughness and cutting forces in AISI 52100 steel using machine learning(Springer-Verlag Italia s.r.l., 2024) Kumar R.; Rafighi M.; Özdemir M.; Şahinoğlu A.; Kulshreshta A.; Singh J.; Singh S.; Prakash C.; Bhowmik A.This study addresses the critical need for high-strength, corrosion-resistant materials in renewable energy, biomedical and maritime applications, necessitating effective heat treatment processes. Focusing on AISI 52100 steel, the research employs finish hard turning with coated carbide inserts under dry cutting conditions. Five machine learning methods are applied to model surface roughness (Ra) and cutting forces (Fx, Fy, Fz) using a Taguchi L36 orthogonal array. Results indicate SVM, XGB, DT, and XGB are superior algorithms for Ra, Fx, Fy, and Fz prediction. Key findings highlight feed rate predominant influence (96.55%) on surface roughness, while depth of cut significantly affects cutting forces. Optimal cutting parameters, 0.1 mm depth of cut, 0.15 mm/rev feed rate, 160 m/min cutting speed, 0.4 mm nose radius, and 40.9 HRC hardness are identified via response surface methodology (RSM) and desirability function. The study underscores the importance of optimizing cutting parameters to enhance surface quality and machining efficiency in challenging material processing scenarios. © The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2024.Item The effect of cardiometabolic control and malnutrition on the prevalence and prognosis of diabetic retinopathy in type 2 diabetes; [Tip 2 diyabette kardiyometabolik kontrol ve malnütrisyonun diyabetik retinopati prevalansı ve prognozuna etkisi](Pamukkale University, 2024) Özdemir M.; Dağ Y.; Uzunlulu M.; Oğuz A.; Ardagil A.; Acar Ö.; Selbest B.Purpose: This study aims to investigate the predictive value of cardiometabolic control, gamma glutamyl transferase (GGT) and malnutrition-related inflammation markers for predicting diabetic retinopathy (DR) prevalence and prognosis. Materials and methods: Type 2 Diabetes Mellitus patients who were consecutively admitted to Internal and Ophthalmology outpatient clinics were included in this study. Clinical, haematological and biochemical data were recorded. Cut-off values of GGT, hemoglobin, albumin, lymphocyte and platelet (HALP) score, nutritional risk index (NRI) and prognostic nutritional index (PNI) scores were determined by receiver operator characteristic curve analysis. Univariate and multivariate analyses were performed to determine the association of all variables with DR. We evaluated which of these tests were predictive and prognostic for the development of DR. Results: This study included 166 patients. Fasting blood glucose (p<0.001), creatinine (p=0.01), HbA1c (p<0.001) and microalbuminuria (p=0.01) were higher in patients with retinopathy. Mean arterial pressure (p=0.01), fasting blood glucose (p=0.03), triglyceride (p=0.008), body mass index (BMI) (p=0.02) and HbA1c (p=0.04) increased significantly as GGT level increased. Contrary to the literature, HALP, PNI and NRI scores were not associated with DR. Conclusion: Duration of diabetes, cardiometabolic control and GGT level are variables with predictive value for the prognosis of DR. No significant correlation was found between malnutrition-related inflammation markers and DR development and stage. © 2024, Pamukkale University. All rights reserved.Item The Effectiveness of Adjuvant PD-1 Inhibitors in Patients with Surgically Resected Stage III/IV Acral Melanoma(Lippincott Williams and Wilkins, 2024) Arak H.; Erkiliç S.; Yaslikaya Ş.; Eylemer Mocan E.; Aktaş G.; Özdemir M.; Semiz H.S.; Kiliçkap S.; Özalp F.R.; Sever Ö.N.; Akdaǧ G.; Aǧaoǧlu A.B.; Özçelik M.; Sari M.; Arcagök M.; Anik H.; Yayla Ş.B.; Sever N.; Açar F.P.; Bayrakçi İ.; Turhal S.; Ayhan M.; Kuş T.Our aim was to assess the efficacy of adjuvant programmed cell death protein-1 (PD-1) inhibitors and compare the other adjuvant treatments in patients with surgically resected stage III or IV acral melanoma. This study is a multicenter, retrospective analysis. We included 114 patients with stage III or IV acral malignant melanoma who underwent surgery within the past 10 years. We analyzed the effect of adjuvant programmed cell death protein-1 inhibitors on disease-free survival (DFS). The mean follow-up was 40 months, during which 69 (59.5%) patients experienced recurrence. Among the participants, 64 (56.1%) received systemic adjuvant therapy. Specifically, 48.4% received anti-PD-1 therapy, 29.7% received interferon, 14.1% received tezozolomide, and 7.8% received B-Raf proto-oncogene/mitogen-activated protein kinase inhibitors. Patients who received adjuvant therapy had a median DFS of 24 (10.9-37.2) months, whereas those who did not receive adjuvant therapy had a median DFS of 15 (9.8-20.2) months. Multivariate analysis for DFS revealed that the receipt of adjuvant therapy and lymph node metastasis stage were independent significant parameters (P = 0.021, P = 0.018, respectively). No statistically significant difference was observed for DFS between programmed cell death protein-1 inhibitor treatment and other adjuvant treatments. Regarding overall survival (OS), patients who received adjuvant treatment had a median OS of 71 (30.4-111.7) months, whereas those who did not receive adjuvant treatment had a median OS of 38 (16.7-59.3; P = 0.023) months. In addition, there were no significant differences in OS observed between various adjuvant treatment agents (P = 0.122). In our study, we have shown that adjuvant therapy had a positive effect on both DFS and OS in patients with stages III-IV acral melanoma who underwent curative intent surgery. Notably, we found no significant differences between anti-PD-1 therapy and other adjuvant therapies. © 2024 Lippincott Williams and Wilkins. All rights reserved.